1. Field of the Invention
The present invention relates to an inspecting method, an inspecting apparatus, and a dimension predicting program of an elastic body with high precision, an inspecting method, an inspecting apparatus, and a dimension predicting program of a piezoelectric/electrostrictive actuator, and an inspecting method, an inspecting apparatus, and a dimension predicting program of a piezoelectric/electrostrictive sensor.
2. Description of the Related Art
Recently, the fields of optics, precision machines, and semiconductor manufacturing require a displacement control device for adjusting the length of optical path and the position of submicron order. In response to this requirement, a piezoelectric/electrostrictive device is developed, including a piezoelectric/electrostrictive actuator using the strain based on the inverse piezoelectric effect or electrostrictive effect upon applying an electric field to a ferroelectric member of an antiferroelectric member, and a piezoelectric/electrostrictive sensor using the charge generation upon applying the stress to the ferroelectric/antiferroelectric element based on the similar effects. The piezoelectric/electrostrictive device uses the charges or electric field induced by the strain of electric-field induction or stress as mentioned above. In particular, the piezoelectric/electrostrictive actuator has features that it is easily controlled for minute displacement, the mechanical/electrical energy conversion efficiency is higher, the power consumption is realized, and these thus contribute to the ultraprecise mounting and to the reduction in size and weight of product. Therefore, the application field might be enhanced.
The piezoelectric/electrostrictive actuator comprises a piezoelectric/electrostrictive operating unit structured by sequentially laminating a bottom electrode, a piezoelectric/electrostrictive element, and a top electrode on one surface of a ceramic base integrally formed by a thick supporting unit having a cavity and a vibrating unit for covering the cavity. In the above-mentioned piezoelectric/electrostrictive actuator, an electric field is generated between the top electrode and the bottom electrode, then, the piezoelectric/electrostrictive element containing a piezoelectric/electrostrictive material is deformed and the vibrating unit is further vertically displaced. The piezoelectric/electrostrictive actuator is applied as an actuator unit of a precision machine using the operation for displacing the vibrating unit. For example, the piezoelectric/electrostrictive actuator controls the on/off operation of a switch or controls the fluid as a micro pump by vertically deforming the vibrating unit.
When the piezoelectric/electrostrictive actuator is used as a switch or an actuator of a micro pump and the amount of displacement is not sufficiently large, the amount of stroke is not sufficient and the piezoelectric/electrostrictive actuator does not function as the switch, or the throughput of fluid is not sufficient in the micro pump. The fluid is not pulled out depending on the case. Further, upon using a set of a plurality of piezoelectric/electrostrictive actuators, the on/off operation of switch is unstable or the throughput of fluid is unstable when the amount of displacement of the plurality of piezoelectric/electrostrictive actuators varies. Thus, the quality of switch or micro pump deteriorates. Therefore, when the same voltage is applied (the same electric field is generated), the piezoelectric/electrostrictive actuator requires the vibrating unit with the amount of displacement that is a predetermined one or more and is uniform. Therefore, when the piezoelectric/electrostrictive actuator is shipped as a product, the amount of displacement of the vibrating unit must directly be inspected by a laser Doppler vibration-meter. However, the entire lots of the manufactured piezoelectric/electrostrictive actuators are inspected and then costs increase. Therefore, in place of this, another inspecting method is required.
Non-Patent Document 1: “Shindo Kogaku” published by Yokendo and first-printed in 1976, in Section 4.6 “Plate vibration” in Chapter 4 “Free vibration of distribution system” (pages 98 to 109)
Non-Patent Document 2: “Kogyo Kiso Shindo-gaku” published by Yokendo and fourteenth-printed in 1989, in Chapter 4 “Lateral vibration of plainer plate” (pages 224 to 228)